Coxiella burnetii (Q fever)

Coxiella burnetii 

• Characteristics
  • Gram negative coccobacilli
  • obligate intracellular
• Transmission
  • Inhalation of aerosolized spores
  • Seen in occupational exposures to farm animals
    • From placental or amniotic fluid of livestock
    • Humans are incidental hosts (not natural carriers)
• Presentation: Q fever
  • Flu-like symptoms (fever, headache)
  • mild pneumonia
  • hepatitis
    • Elevated ALT and AST
  • May cause culture-negative endocarditis
• Diagnosis
  • Usually clinical; although may be supplemented with testing
  • Blood cultures usually negative
  • Immunofluorescence assay for IgG against Coxiella is used to confirm diagnosis
• Treatment
  • Doxycycline is first-line
    • TMP-SMX given if doxycycline is not tolerated
    • Hydroxychloroquine may be added with cardiac involvement